Last June (2012) marine mammal researchers and stewards around the Pacific Northwest were surprised to learn of seismic research cruises that would use air guns to survey faults and crustal structure on the outer coast of Washington and Oregon. Our concern was that there would be inadequate mitigation of potential acoustic impacts on marine species (particularly southern resident killer whales). It all happened very fast and I never heard much about how it went… until now.
Thanks to John Dorocicz who has been logging acoustic highlights from one of the hydrophones maintained by NEPTUNE Canada near the head of Barkley Canyon, I just had the rare opportunity of hearing airgun blasts in the real ocean — complete with simultaneous vocalization of nearby dolphins. The date and time of the recording match up very well with a cruise track of the R/V Langseth, the research vessel from Columbia University’s Lamont Doherty Earth Observatory.
Here’s where the Barkley Canyon hydrophone is located:
Here’s where marinetraffic.com AIS shows the Langseth was at 8:25 UTC on 2012-07-19, about 175 km south of the hydrophone.
And finally, here is a spectrogram of two seismic blasts recorded at 10:13 on the same day, along with sounds from (likely Pacific White-sided?) dolphins.
Listen to the recording and you’ll notice the low-frequency rumbles of the airgun blasts along with what seems like an increase in dolphin vocalizations (visible as wiggles at 4-6 kHz in the last fifth of the spectrogram). I wonder if these were the first two blasts the dolphins experienced. If so, then the suggestion (made by John initially) that the dolphins are responding to the blasts seems tenable. But were there many blasts before this recording was made? And why wouldn’t they react as much to the first blast in this recording as they seem to react to the second blast?
Regardless of the answers, it is exciting to hear what airguns sound like on Washington’s outer coast at a range of nearly 200 km. The number of marine animals exposed to the sounds of seismic exploration is staggering and begs the question: is the risk of interfering with so many oceanic lives worth knowing more about the subduction zone that may someday rock our west coast cities?
Live blog from the third and final workshop on “Evaluating the Effects of Salmon Fisheries on Southern Resident Killer Whales” that begins today (9/18/2012) in Seattle, WA. The workshop runs Tuesday-Thursday (9/18-9/20). During this third step in the process NOAA initiated to manage chinook salmon with attention to southern resident recovery, a U.S.-Canada science panel will hear comments on their draft science plan along with new presentations of data and analysis that may improve the plan.
Exciting aspects of the workshop III agenda are presentations by Mike Ford on diet and distribution of SRKWs, Sandie O’Neill on contaminant and stable isotope insights, Sam Wasser on hormone analyses, John Durban on growth and body condition, and Dawn Noren about energy requirements.
Most presentations (will) include links to the slides (PDF or PPT) archived on the workshop web site. Select presentations also include a link to the audio recording of the presentation.
Day 1 (Tuesday, 9/18/2012, 8am-5pm)
8:16 Pat of WA Dept of Fish and Wildlife comments (mp3)
- Generally agree with draft report regarding the low impact of extant fisheries on killer whale recovery.
- But, in sections 5.2 and 5.3 the report mentions the distribution of “far north-migrating” Chinook stocks. Coded wire tag and genetic data from off WA coast show that many stocks are present, including: Sacramento and Northern Oregon coast. Columbia river summer chinook do sometimes wander into the Strait of Juan de Fuca or the San Juans.
- Need more data on winter distribution of SRKWs.
- There maybe thresholds effects, but they may be hard to detect.
- Eric Eisenhardt comments:
- SRKWs did go north of Vancouver island twice this summer, so that confirms they are foraging outside of Puget Sound and the Northwest Straits
- L-112 Victoria/Sooke had both Chinook salmon and halibut in her stomach.
8:36 John Carlisle of Alaska Department of Fish and Game comments (mp3)
- Growth rate criteria may not be the best metric for recovery. The growth rate will ultimately decrease as the population reaches carrying capacity. If you go to an abundance-based criterion, you’d conclude that the population is going to recover. Since the aquaria removals this population has been recovering.
- Comment from Ken Balcomb (cutting through the smoke and mirrors): if you choose any decade other than the mid-70s when the population was at its lowest, the SRKW population is in decline, not growing. There were 100-120 before the captures; there are 84 now. That’s a decline in my book.
- Comment: we ought to look at where these animals in every month of the year.
- Mamorek and Ford: we are not being consistent yet about defining each season.
9:01 John Ford of Northwest Fisheries Science Center comments (mp3)
- Reminded audience of workshop I and II data showing movements along outer coast at least from January through July.
- Diet information was under-emphasized. We had more than two samples and we have new data.
- Report makes overly simple assumptions about seasonal distribution
- There is seasonal overlap of whales and Chinook stocks (they don’t feed only in the Salish Sea during the summer).
- We need to be very clear about seasons and could look at shorter-time-scale overlap.
- Not all versions of Ward’s lambda are comparable with the recovery growth rate criterion.
- Comment discussion (Bain, Durban, Ward) of whether the SRKW abundance time series shows density dependence or not.
9:22 Department of Fisheries and Oceans comments (mp3)
- the panel inference of increase (rather than decline) is stronger than warranted given inherent uncertainties (ref Velez talk later this morning)
- causation is evidenced by multiple lines, including CPUE declining with decreased Chinook abundance
- Winter ecology could benefit from synthesizing information from w0rkshops 1 & 2, including all new acoustic and visual observations.
- Diet data for Dec-Apr are scarce, but Chinook still appear to be primary prey.
- Statistical design of diet studies should be undertaken
- Fisheries and prey availability
- Vast majority of Chinook eaten May-September are Fraser Stocks, but only weak association between terminal run of Fraser Chinook and SRKW vital rates. Why? Low quality data on Fraser Chinook? Abundance of Fraser Chinook may be sufficient for current SRKW population size.
- Scordino question: why isn’t satellite tagging being done in Canada? John Ford: we’re focusing on acoustic detections along outer coast to get better sense of timing during off-season periods.
- Balcomb question: wrt statistical sampling — our scale and fecal samples are really only collectible during low sea states; those samples are/will-be difficult to obtain during the winter months offshore.
- Marmorek question: Why isn’t there a stronger association between Fraser Chinook time series and vital rates? We’re not sure, but there is a strong correlation between coast-wide Chinook abundance and vital rates… Led to discussion of correlations… Mike Ford summarized by saying there’s no single stock that’s better than the coast-wide abundance index.
10:20 Antonio Velez-Espino — Killer Whale Demography (mp3)
- Selected 1987-2011 demographic data [10 years less than Ward!], used 7 age/sex categories [different than Ward's!), and defined lambda as the asymptotic population growth rate
- SRKWs have greater vital rate variability, lower fecundity, and higher mortality, and higher proportion of post-reproductive females -- compared with NRKWs.
- SRKW are in mild decline of -0.91%, while NRKWs are in annual increase of 1.65% (which is below the current SRKW recovery criterion!)
- 48 individuals were captured or killed according to Olesiuk
- Greatest effect on vital rates is due to young female survival
- Maximum increase in pop growth is produced most by young and reproductive female fecundity.
- Greatest increase to lambda (pop growth rate) comes from avoiding reductions to survival of young reproductive females and increasing their fecundity.
- Comment: why did you start with 1987? Answer: this was a compromise between extent and highest quality data that is most representative of the current population ~25 years or one generation back.
11:00 Mike Ford Review of southern resident diet information by season (mp3)
- Cloning and high-throughput sequencing (extract DNA from homogenized and pooled from about 1000 prey samples and 300 fecal samples from a period of years (Jan-Apr not well represented); use primers for potential prey, not SRKWs; use reference and custom data bases of 40,000 DNA sequences; post-processing to remove chimeras) which has potential sources of bias (from collecting to relative tissue density of mitochondria, digestion factors, PCR amplification differences)
- Results: May-July dominated by chinook; Aug-Sept include some sockeye and coho; Oct-Dec mostly chum (~3x more chinook than chum in Oct and Dec, but ~2x chinook more than chum in November); 2005-2008 August was highest proportion (~15%) of sockeye (Chinook made up the rest); Most fish were year 2-4, but some younger during winter in Puget Sound.
- Jan-Mar only a handful of samples, but almost entirely Chinook.
- Is this a summary of Salish Sea only? Yes, all fecal samples for summer months are from inland waters, though there are some samples (from John) from the outer coast...
- Q: John Ford -- Have you looked at samples that may contain prey transported by SRKWs as they return from an excursion to the outer coast. A: no due to budget constraints we have combined samples to look at average patterns.
- Mike Ford: We haven't tried to quantify the levels of DNA in the fecal samples from L-112, but we have detected Chinook and halibut.
- Ken: wrt oct-dec sampling, all three pods were in the area during that point
- Tim from NOAA fisheries: 2010 was our world record sockeye year. Mike: we sadly have no samples from those months in that year. Tim: there are blackmouth present during chum runs.
11:21 Sandie O'Neill Integrating stable isotope, genetic, and scale samples... (mp3)
- These methods differ, but are complimentary (stable isotopes average longer spatial and temporal scales)
- D. Herman studied stable isotopes of KWs and prey that provide TEFs that help interpret our mixing model which shows SRKW stable isotope signatures along the "salmon line" in a location that our "classic" model says is associated with a diet in late summer of 43% Chinook (scales suggest 70%; fecal suggest range...)
- An "alternative" model gives more weight to known prey choices and lets us ask what would TEFs need to be for results to be consistent with scale and genetic data?
- 52 scales samples (NWFSC only) (2004-2008?)
- Estimated diet with scales (no genetic prior) = 72% median Chinook proportion
- Median nitrogen TEF 1.65; carbon 1.18 (lower than reported)
- Main result from all models: Chinook is dominant in September, but proportion is a little lower than expected.
- Time-frame represented by biopsy samples (from about 12 of about 30 available SRKW samples) were selected to be from period of Aug-Sep, but we don't know over what time scale the sampled isotopes are influenced...
- SRKW eat more juvenile Chinook than we think
- SRKW eat some other lower trophic species that's not detected well in prey and scale samples (possibilities: BC halibut is left of salmon line; lingcod, rockfish, herring, and English sole are all to right [higher deltaC%])
- SRKW eating more chum, sockeye, or steelhead than are apparent in the scale samples
- Isotope turnover rate is based on bottlenose dolphin skin growth rate of 72 days.
- John Ford: 2 stranded SRKWs on outer coast showed stomach contents consistent with Chinook and squid. Have you looked at their stable isotope signature?
- John Durban: might fasting affect isotope ratios in the skin biopsies? Dawn: mammals usually metabolize all fats before affecting proteins.
- Daniel: trophic fractionation data may help with your mixing model (KWs are like most terrestrial predators ~3-5 for nitrogen)
- Scordino question…
12:00 lunch break
13:21 Sandie O’Neill — Using chemical fingerprints in salmon and whales to infer prey (mp3)
- Contaminants in fish (POPs = PCBs, PBDEs, hexachlorobenzenes (HCB), etc.)
- How do west coast Chinook salmon populations differ in POP concentration (about 30 fish from each of Skeena, Fraser (S. Thompson, upper/middle Fraser; no Harrison yet), Columbia River, Sacramento/San-Juaquin; about 80 from Puget Sound)
- Puget Sound PCB levels about 4x higher than other sites (~60 ppb and highly variable — 10-210 ppb, migratory-resident); sub-adult residents ~140 ppb mean…
- Multi-dimensional scaling plot (4 POPs) show similarity of samples: groups show Skeena is more distinct from CA, than Fraser is distinct from Columbia, with distinct and bimodal Puget Sound Chinook. Herring show similar geographic grouping of this pelagic signal, but benthic species show more local non/urban-patterns.
- K/L pod fingerprints overlap with CA/Columbia fish; J pod overlaps most with Puget Sound non-resident Chinook.
13:50 Michael Ford — Overlap of southern resident killer whales and Chinook salmon (mp3)
- What we really want is overlap of SRKW and Chinook along west coast over time.
- Figure from first workshop: Daily SRKW (all pods, and J pod alone) sightings 2003-9 is above 75% for May-July, above 40 in Aug-Oct.
- K/L pods not showing up more than 50% of the time until June
- Slide with inference of time spent in regions offshore of CA, OR, WA, BC by Ken B (too small to see values)
- Acoustic recorders of Brad and John show SRKW (mostly K/L) detections per unit effort peaking at 10% during Jan-Mar at Columbia, but also significant during winter as far south as Point Reyes. Riera plot shows seasonal pattern of NRKW and SRKW at mouth of Strait of Juan de Fuca.
- Summarizing whale distribution
- July-Sept 56% of time inland; 44% in western straits and Vancouver Island
- April-June — 70% outer coast (~19% of days accounted for with PAM/NOAA — 65% centered on Columbia, 30% near Tatoosh, 5% south of Columbia.
- Oct-Dec 81% outer coast, 19
- Jan-Mar 96% (missed north-south breakdown), 4%
- Chinook distributions (Weitkamp, 2010, coded wire tag data; May 2010 genetic data from WDFW, NMFS, DFO not covered here much but consistent with CWT results)
- Summer — 56% inland; 44% western straits (more than 100 tags annually from lots of stocks — central BC to CA, including Columbia)
- Spring — 68% of time outer coast (65% off Columbia to Olympic coast; 30% western straits; one more…)
- Winter — 75% outer coast (75% Columbia/WA) 4% puget sound [Only about 6000 tags over 40 years of CWT effort; compare with summer total of ~110,000]
- Fall — 81% outer coast
- Whales spend ~40% of time west of Strait of Juan de Fuca
- April-Dec SRKWs overlap with all major stocks south of central BC
- Jan-Mar very limited salmon data
- Ken Warheight WDFW samples from Chinook ocean troll fisheries off WA coast show 2011 May-Aug show lots of Columbia stocks, and other (mostly Oregon)
- WCSGSI Collaboration by Pete Lawson and Renee Bellinger show genetic data: similar stocks present off OR coast.
- Furthest south J pod has been detected on acoustic recorders is Westport.
- Comment from Dave _____: CWT data show salmon distribution where fishing occurs, not necessarily their natural distributions; same commenter said “Columbia stocks spend their entire life history in the range of the SRKW” (!). The north OR coastals come in June when SRKWs are mostly in inland waters. M.F.: One of my main points is that in June, and especially May, K/L pods are spending at least half their time on the outer coast.
14:22 Antonio Velez-Espino, DFO — Role of ocean and terminal run abundance of Chinook salmon on Resident Killer Whale population viability (mp3)
- 1: Main hypotheses (based on diet evidence)
- 1a. SRKW growth influenced mainly by terminal run size of Fraser Early, Fraser Late, and PS Chinook
- 1.b NRKW Northern BC, Central BC, WCVI…
- 2: Additional hypotheses (assuming Chinook remains important diet component year-round) relate to stock size, spatial overlap, and temporal overlap
- 2a. SRKW growth influenced mainly by terminal run size of abundant stocks
- 2a. SRKW growth influenced mainly by ocean (pre-terminal) abundance of ocean-type stocks with large contributions to ocean fisheries
- Again using 1987-2011 RKW abundance and vital rates, Kope-Parken terminal run size, CTC Cohort ocean abundance, simple * mulitple linear regression models
- Some support for 1a and 2a; interestingly, most interactions occur with female 2 fecundity (old reproductive females)
- Interactions with Puget Sound ocean abundance and young & old reproductive females; and WCVI are most important. (Both are selected for fisheries scenarios)
- We, too, were surprised that the Puget Sound ocean abundance seems to be more important to SRKW population growth than the Fraser river stocks. It may be that there are confounding factors (e.g. toxins) or it may be we don’t have enough data to resolve what may be weak signals.
14:52 Sam Wasser — Why physiology matters (mp3)
- Challenges to assessing recovery (3)
- Physiology is a bridge — dynamic changes can be captured by allostatic load; reproduction can be suppressed by physiology.
- Having many factors influence a given hormone is a strength!
- Endangered caribou example
- SRKW results (4 years)
- GCs increases with psychologial and nutritional stress
- Thyroid T3 decreases with nutritional stress, but changes more slowly than GC
- Hi Thyroid corellates with high birth rates and low death rates
- The more Chinook at the Columbia (or Fraser) river, the higher the mean T3 level
- We get 150 POP samples/year (compare with O’Neill’s 30 biopsy samples) showing, e.g. PCB/DDT ratio for K/L pods is always much lower than for J pod
- If fish matters most, recovering fish should be top priority (maybe not fisheries, but Habitat!)
- Timing of run may be key (delaying fishery may help)
- Measuring physiological response over time could also indicate how things improve in response to mitigation
- Few tools can offer that
- During last workshop, L10 (L90?) was thought to be injured. We’ve already resolved that she was pregnant and aborted!
- There is tremendous variability from year-to-year in Fraser (Albion, 2007-2011; 66k-242k). In a year when there are long delays in the Fraser peak (near Julian day 240), it may be devastating if
- Andrew Trites comment regarding possibility that thyroid data could be interpreted differently (referenced their captive starvation experiments and some studies in wild).
- Lance Barrett-Leonard comment: we historically have observed that RKWs arrive in a condition of relative nutritional stress — e.g. ketosis, more foraging earlier/ more social later.
- Comment: upper Columbia river stocks (Bonneville) aren’t caught in any ocean fisheries; lower Columbia and Willamette stocks are more impacted by ocean fisheries.
15:53 John Durban — Size and body condition of southern residents (mp3)
- Review of last fall’s results along with new analysis
- New analysis regarding two comments made by NWFSC that suggest there has been a misunderstanding:
- photogrammetry of Durban et al 2009 has high error rates.
- photogrammetry did not detect that L67 was near death.
- We used boats of known length to quantify bias of ~7cm at altitude of 1000′
- But when we’re measuring distance ratios (relative shape), e.g. length/width, within the same photograph, altitude does not matter. Width is harder to measure than body width due to waves at edges of body, so we used head width/length to gauge error rates; average coefficient of variance only 0.03. L67 was only 0.12 when average female was ~0.135.
- Latest efforts are looking at whole body shape differences between whales
- L67 jumps out as having “peanut head” and anomalously thin peduncle
- J14 and J17 were measured when around 12 months pregnant and found the peak of their width came aft of their dorsal fins.
- Pitman et al, Journal of Mammalogy 88 demonstrates with Antarctic KWs where we hope to go with SRKWs.
16:16 Dawn Noren – Energy Requirements and Salmon Consumption by Southern Resident Killer Whales in their Summer Range (mp3)
- RKWs (both N and S) are larger than Icelandic KWs (from which captive KWs have been used to get estimated length at age from time series data)
- Best estimates of asymptotic body length of SRKWs come from captive Islandic whales — Females 630 cm; males 700 cm — and are also consistent with the initial photogrammetry results of Durban (when corrected by 80% factor?)
- There are some times when SRKWs are estimated to consume upwards of 50-60% of some runs
- Two approaches to determine SRKW DPERs yield similar results.
- Two approaches (Williams vs Hanson) do differ slightly…
16:40 General discussion (mp3)
- Ray Hilborn question: is there scientific consensus about an annual cycle in killer whale condition?
- Durban confirms that later in the summer social behaviors that create better grouping for photogrammetry
- Barrett-Leonard makes another supporting point…
- Bain mentions that other patterns suggest early stress (travel speeds get higher, echolocation rates higher)
- Wasser suggests that they seem to have had their most energetic feeding of the year in the early spring; he may have said “best body condition,” but meant most energetic feeding.
- How do we make population inferences from studies of individual whales.
- Sam: it depends on number of samples you’re getting.
- Longer discussion with comments from Ken B., Fred F., Dawn N., Lance B-L. (behaviors like prey preference and inertia are important), John D. (we should indeed reflect more than we have on our inferential framework).
- Another panel member suggests it may be fruitful to conduct a meta-analysis of other populations (e.g. for population significance of a female that has a 100% offspring mortality).
- John Ford suggests comparisons with transients would be useful, but we lack the detailed census information and behavioral observations we have for residents.
- John Durban mentions recent completion of study of a few *thousand* resident KWs from northern climes (often feeding on acker-mackerel(?)) leads him to think that SRKWs are indeed unusual residents.
Day 2 (Wednesday, 9/19/2012, 8am-5pm)
8:00 Intro (mp3, latter portion only)
8:17 Ken Warheit, WDFW — Genetic composition of recreational catch from the San Juan Islands (mp3)
- Genetic Stock Id (GSI/PSC-CTC GAPS baseline) analysis, age, fork length from 450 Chinook taken from 2009 San Juan Islands recreational fishery
- Stock composition is different from SRKW diet (sampling in different years, though)
- No diff in size and age distribution between Fraser and PS stocks (including hatchery)
- SRKWs not using some areas where humans catch large Chinook (from Puget Sound)
- 3 basic stocks: Fraser (101, 96 wild), Puget Sound (297, 51 wild), Other (47, 31 wild).
- Most overlap in human and orca (Hanson samples) are Hein Bank to Henry Island; orcas not catching (or Brad not sampling) as much as recreational fishers inside east San Juans or Rosario; no fishers reporting from Pt Roberts area where orca prey samples were obtained.
- Lummi Chinook bycatch in their sockeye fishery report mostly Fraser Chinook in Pt. Roberts/Alden Bank area.
- Chinook proportions are much lower in recreational catch than in orca samples, with greatest difference in July (all areas of San Juans ~10% Chinook)
- Fork length vs age: mean length ~55 cm in age 2, 70 age 3, 80 age 4, 90 age 5 (legal limit ~52)
- In each area the same age class are about the same across 3 main stock groups.
- There appears to be a difference in
- Comment Tim of NOAA: sockeye migratory corridor changes from Rosario to Haro from year to year. Do Fraser Chinook do the same? A: The main reason there are proportionally more PS fish caught in Rosario area is that there are many more PS fish there; there are, though, some Fraser fish are present there. Tim: Skagit fish mill in the Anacortes area.
8:47 Robert Kope, NOAA — Effects of fishing on availability of Chinook salmon to resident killer whales (mp3)
- Harvest impacts make up more than 20% of the “Parken-Kope” indices
- The indices don’t account for immature (age 3-4) fish not killed by fisheries.
- On average, these immature fish account for more than half the total abundance in the ocean.
- How appropriate is the 20%? Harvest impacts account for 33% of the aggregate PK index.
- What matters to the killer whales is the local density where they’re foraging. Abundance may be sort of irrelevant to RKWs. Overall, 20% seems like “a reasonable ball-park number.”
- Bain question re whether immature fish are important to SRKWs that seem to prefer largest fish?
- Alison question: Should we be considering outside stocks more? A: The fall aggregate mostly consists of outside stocks.
- Panel question: Can we clarify salt-water age versus fresh-water age 2-5 terminology? A: Most stocks except Fraser spring Chinook have ocean-type (vs stream-type) life history.
- Another public comment re Upper Columbia River Chinook not being available in the ocean fishery.
- Larry Rutter comment: we should be very disciplined about the nuance between harvest rate and exploitation rate. A: Within a small group of the Pacific Salmon Treaty, there is a distinction harvest rate is “a reduction in the number of fish that are available.”
9:14 Robert Kope, NOAA (again) — Assessment tools for evaluating effects of salmon fishery management on resident killer whales (mp3)
- Fishery assessment tools — FRAM vs CTC — use similar algorithms and ~95% same data.
- Exploitation Rate Analysis (ERA) uses coded wire tag recoveries by brood year, typically available a year out (e.g. 2012 ERA used CWT data through 2010)
- ERA, GSI, and Parken-Kope are retrospective
- CTC, FRAM are both retrospective and prospective
- Mark-recapture is the “gold standard” for estimates of escapement numbers which are used as model inputs.
- Panel question: I’m concerned that we have model predictions with CVs of 50%. Ward A: forecasting beyond ~5 years is difficult.
- Panel question: Is KW predation changing the natural mortality rate in a way that the FRAM model doesn’t capture because it uses a fixed natural mortality rate?
9:42 Antonio Velez-Espino – Chum salmon as a covariate of Resident Killer Whale population viability (mp3 | video)
- Using BC and WA terminal runs of chum
- Highest elasticity was for interaction between Puget Sound salmon stock aggregate and fecundity of young and mature reproductive females
10:40 Eric Ward — Estimating “other” marine mammal effects on salmon with limited data (mp3 | video)
- How much to seals and sea lions compete with SRKWs?
- Best U.S. data: harbor seal surveys (Jeffries et al., 2003); Canadian and other data sources have data gaps…
- Panel suggested using Ecopath modeling results, but Eric has no confidence in model outputs.
- Instead cite A. Acevedo-Gutierrez work or citations in his papers.
- Better approach: multivariate state-space modeling using MARRS R package (Holmes+ 2012)
- Essington & Quinn have survey data going back to 1930s/1940s, but data are messy.
- Harbor seals are eating more juvenile Chinook than adults.
10:56 Scott Pearson, WDFW — Competition from Pinnipeds (mp3 | video)
- 3 pinnipeds overlap in range (but not necessarily time and niche)
- Harbor seals: reaching carrying capacity in ~1990s (Jeffries, 2003)
- California sea lions: all males in pulses from southern colonies
- Stellar seal lions: population growing and continuing to grow in SRKW habitat
11:17 Lynne Barre & Eric Ward — Summary of lambda & Killer Whale growth rates (mp3 | video)
- Delisting criteria: mean growth rate of 2.3% per year for 28 years
- Info about population structure and behavior that is consistent with resilient (e.g. shorter inter-birth intervals)
- Data supporting criteria
- 1974-1980 mean 2.6%
- 1984-1996 mean 2.3%
- NRKW 1974-1991 3.4%…
- Some have suggested abundance criteria instead of growth rate…
- If you achieved growth rate of 2.3% from 81 whales in 2001, you’d get to 155 whales in 28 years (in 2029) => delisting
- for 14 years you’d get 113 whales in 2015 => downlisting
11:23 Ward swaps with Barre, summarizes past lambda results, and presents discussion questions (starting ~11:30)
- Mike Ford Q: extinction risk was influenced most by catastrophic events, so maybe an alternative de-listing criterion could be a threat criterion. Lynn A: we have quite a few threat criteria already.
- Panel comment: Given the uncertainty in the historic population size, let’s say you used 1/2 carrying capacity. The estimates I have would put abundance at high 90s or even as high as 300. Ward A: one solution would be to optimize carrying capacity and growth rate. (balance productivity and abundance). In fisheries those are Kobe plots — exploitation rate and abundance are axes…
- Larry comment: Back in Poet’s Cove, we asked “what’s the best think we could do for southern residents.” The answer was take care of Fraser salmon. Now it should be take care of Chinook salmon. Lynne response: one of our three components to the recovery plan is recovery of the prey populations.
- Bain comment: An alternative is a recovery budget that starts with trying to conserve genetic diversity. At 3% growth, you lose 6% genetic diversity per generation. If you stay stable, you lose 25%. If you decline as in 1990s, you lose 50%. I’d like to see actions that try to achieve that 3% growth as soon as possible (WW impact reduction is fast but has short effect; toxin reduction is slow but has long effect; salmon recovery actions have a wide range that could be pieced together to get optimum evolution of population growth). Lynne A: there is a table in the recovery plan that is a basic approach similar to what you’ve mentioned. Dave: Incorporate a time frame into that.
- Scordino Q: if you met your recovery goal and got up to 155 and then did your PVA would you still call it an endangered species? Lynne: I don’t know.
- Scordino Q: if population stabilized and we determined the carrying capacity had been reached, would the SRKWs be delisted? Lynne: I can’t answer that now.
- Mike Ford: We should tie recovery to risk of extinction, not carrying capacity metrics.
12:00 Lunch break
13:15 Questions from panel (mp3)
13:23 Eric Ward — Other approaches to adjusting Chinook abundance (mp3 | video)
- Scenarios involving raising P-K index by 10%…
- Why not other P-K indices? Best predictor is total index (aggregate of all salmon stocks), implies that no one stock is important in all years
13:36 Antonio Velez-Espino, DFO – Resident Killer Whales population viability analysis under selected fishing scenarios (mp3 | video)
- 4 scenarios
- Under status quo, the ime for quasi-extinction of SRKW (population falling below 30) at median probability is ~50 years.
- Under all scenarios, the probability of downlisting is always zero under U.S. criteria.
- Only under most extreme (fishing reduction) scenario does the SRKW growth rate become positive!
- Hypothesis 2a: closing WCVI fishing only increases growth rate by ~0.5%
- 75% reduction in ocean harvest rates of Puget Sound stocks also only results in ~0.5% growth increase
- Is Chinook abundance limiting population growth and viability of RKW?
- We need more research to understand depressed SRKW calf survival (relative to NRKW)…
- First report will be available in February.
- Panel comment: This seems opposite of what Eric Ward found. You’re saying they’re going to go extinct. A: Yes, unless dramatic change is made in fishing impacts, based on this time period we have chosen in which population is in decline.
- Peter Olesiuk’s census data is of high quality for individuals during the period we chose.
- Lots of discussion, primarily around why these results are different from Eric Ward’s.
14:23 Panel presentations about causality vs correlation (mp3 | video)
15:20 Last question
What are most critical data needs and analyses to reduce key uncertainties affecting management decisions? What types of evidence to alter/strengthen conclusions?
- Better estimates of Chinook abundance (not just indices), ideally where SRKWs are foraging
- Columbia river springs are not in the indices!
- What is relationship between contaminant loads and vital rates?
- How important is inter-specific competition (to vital rates)?
- How do SRKWs locate and catch salmon and how is their foraging efficiency affected by noise and/or interference?
- We need tools to detect nutritional stress in advance of changes in vital rates.
- Year-round satellite tagging
- Go to empirical data on Chinook (especially Fraser); Parken is pioneering GSI in conjuction with test and high-seas fisheries.
- Chinook density and stock identification at times and places where SRKWs are foraging.
- Better salmon forecasts using marine ecosystem indicators.
- Statistical power analysis, once Eric and Antonio have come to agreement about the base period for assessing growth rate.
15:43 Science panel and panelist discussion (mp3 | video continuous w/previous)
- Schindler: We should be considering alternative hypotheses, e.g. disease
- Trites: Periods of low abundance seem important (not the summertime), so when/where are they occurring?
- Hilborn: In some species, social interactions control growth. Also, the differences between N and S that are more interesting than the apparent correlations
- Science panelist: It appears to me that NRKWs are first in line during the return migration of U.S. Chinook. Ford: Good point. About a 1/3 of prey samples we got from NRKWs near Haida Gwai were Columbia Chinook.
- Jim: Why were Chinook populations low during 1990s? Dave: lowest in my experience was in 1970s prior to the Salmon Treaty. Jim: There was a regime shift in 1970s that led to growth in many marine species and around 1989 another shift caused many declines. The Gulf of AK ecosystem has been doing better recently than the CA current system, so N/SRKW populations are really.
- Eric Ward: habitat and dams are not on the table (for this workshop)!
- Panelist: stochastic events like ship strikes (of calves) may be obscuring correlations, so perhaps hormone and other techniques should be used to detect pregnancies and get at neonate mortality (especially in NRKWs which are rarely observed in winter).
16:10 General discussion (mp3 & video continuous with previous)
- Sam Wasser: overall these analyses have been too coarse and should pay more attention to the annual cycle of interactions between SRKWs and salmon.
- Brendan Cummins, CBD: I don’t understand the general vibe that reducing fisheries won’t make a difference. My reading of Antonio’s model was that reductions could lead to halving of extinction risk.
- Mike Ford: The size of the effect depends on the metric you’re using, so “negligible” on lamba could mean a whale per year for the population. What 3rd factor couldn’t involve the predator-prey interaction? Understanding the differences between NRKW and SRKW are the key to discovering how to help the SRKWs recover.
- Lance Barrett-Leonard: A justifiable management option (without being sued) is actions that reduce fishing pressure during low abundance years. I hope the panel’s final report does not just consider regulation of particular stocks.
Day 3 (Thursday, 9/20/2012, 8am-5pm)
8:30 Larry Rutter final remarks (not recorded)
8:42 Will Stelle final comments (mp3)
- The predator-prey interactions of listed Chinook and listed orcas put up a huge red flag for many state, tribal, and Federal co-managers because of the potential management implications.
- I didn’t know what to expect from this high-risk meeting, but I recall how quiet and responsible it was. There were no histrionics. There was no table pounding.
- Thanks to the science panel for credible examination of best available science. Thanks to the sovereign governments that surprisingly stayed focused on this tough subject.
My case study for this week centered on reducing bycatch of juvenile red snappers by shrimp trawls in the Gulf of Mexico. The paper is: Designing marine reserves to reduce bycatch of mobile species: a case study using juvenile red snapper (Lutjanus campechanus), by Diamond et al.
Red snapper from the Gulf of Mexico
The research team made use of geographic information system (GIS) to map fishery-independent trawl surveys done by the Southeast Area Monitoring and Assessment Program (SEAMAP) every summer and fall in the Gulf of Mexico from 1987 to 1997.
The paper attempts to asses whether there is a geographic pattern to the distribution of juvenile red snappers.
Diamond et al. analyzed juvenile red snapper distribution and examined “hot spots” with high concentration (intensity) and the predictability for the hotspot to reoccur in the same position over time (persistence). In designing marine reserves, one could designate no-trawling zones according to the desired level of intensity and persistence which correspond to percent or numerical bycatch-reduction goals.
In further consideration, given that red snappers are highly mobile and higher-intensity hotspots are often unpredictable, a no-trawling zone does not need to be permanent. Ideally, such a no-trawling zone could be fluid from year to year, in order to avoid trawling in higher-intensity hotspots.
For a no-trawling zone to be fluid, it would depend on how effectively this information could be disseminated in a timely manner. This could also apply to marine vessel no-go zones in the activity range of Southern Resident Killer whales. In the San Juan community, dissemination of information should be relatively easy due to wide availability of communication technology.
How did San Juan Island really look like 200 years ago?
Last Friday the S Pod had a case study discussion on sustainability. I chose an article entitled “Global Consequences of Land Use” by Foley et al, published in Science in November, 2005. The article pertains primarily to the effects of agricultural land use on land cover. One aspect I find intriguing is soil salinization, a phenomenon common in agricultural lands. Heavy irrigation of soil, coupled with removal of deep-rooted native vegetation, cause water table to rise near to soil surface. A disturbance such as heavy rainfall can then draw water levels to the root zone. When this water is evaporated from the soil surface, the salt is left behind, causing soil salinization, which quickly deteriorates soil quality.
Our Beam Reach instructor, Dr. Scott Veirs, mentioned that one common problem on San Juan Islands is the overwithdrawal of groundwater, causing salt water to seep into the aquifer. This led me to think more about the land and resource usage on San Juan Islands. In a conversation with Jason Gunter, owner of Discovery Sea Kayak, I found out that before English and American settlers arrived at San Juan Islands, the Native Americans practised controlled burning of open lands in order to better harvest bulbs. It has been speculated that at the time, many parts of San Juan Island were not forested. The theory is that controlled burning allowed slow-growing trees such as oak to mature. When controlled burning stopped, tall and faster-growing conifers such as Douglas fir out-competed the slower growing species by creating shades. These conifers propagated, which gradually brought about the landscape we see on San Juan Island today.
Jason has also mentioned that this change in land cover has caused the loss of a few species of birds. It would be very interesting to find out how land use and land cover have evolved for the past 200 years, and whether this has impacted the local nearshore or marine ecology in any way. Nonetheless, I think it is even more pertinent to study the current land and resource usage on San Juan Islands, in order to modify and adapt resource usage to ensure the continuous availability of these resources — such as potable water and fertile soil — in the future.
This week the S Pod, as we Spring 2012 Beam Reachers are now called, discussed at length about “sustainability science”. So, what is sustainability science? Each of us has a unique definition of what sustainability means to us, and many writers have proposed a variety of definitions.
My personal definition of sustainability has its foundation in the very meaning of the word “sustainable”. The word sustainable connotes, first, the “capability to be sustained”, and second, “using a resource such that the resource is not depleted or permanently damaged”.
In implementing a “sustainable project”, it is important to make sure the project can be continued on a long-term basis. I recently visited a rural village in the Samburu region of Kenya, where NGOs have installed water filters for rainwater reservoirs. However, when I was there, the water filters were not functioning because the NGOs had failed to adequately educate the local community in how to properly use the filters. Therefore, one could say that this project is not sustained, and such a project is not sustainable if the local community does not get involved.
How does the above example translate to sustainability science, and in our case, environmental conservation? One of the most important element in sustainability is education. By imparting the knowledge and idea pertaining to one’s project to the local community, the local people could then become the engine of the project, and these knowledge, ideas and good practices could hopefully be passed down to the next generation and inspire students to become field-level experts.
Two days ago, Katie Fleming from REsources, an NGO based in Bellingham, WA, shared her experiences in community outreach. She implements a model which she calls “community-based social marketing”. This model markets an environmentally friendly idea or practice, such as to turn off the engine when the car is stopped for more than 30 seconds, by educating school children to influence their parents, giving small incentives, and by adding a “peer pressure” element”.
I feel that this is a wonderful practice in sustainability, in both aspects of ensuring the project is sustainable, and in promoting a more sustainable use of resources.
Moving on to the second definition of sustainability, which is the sustainable use of resources. The household definition of “sustainability” usually refers to the popular concept: to make use of renewable resources, and to reduce, reuse and recycle consumer products. One aspect of sustainability science could be to use a research method that is in line with the above practice, so that the research could be economically sustainable and have minimal impact on the environment.
Sustainability science in a larger scale would be to examine the current state of environment, and to encourage essential economic practices such as agriculture and transport, to move towards the sustainable use of our shared natural resources.
Our Beam Reach instructor, Dr. Robin Kodner shared with us her personal definition of sustainability during our round-table discussion. One of Dr. Kodner’s current research project is to measure the level of Domoic Acid, a neurotoxin produced by the diatoms Pseudo-nitzschia, in nearshore waters. Her hypothesis links higher levels of Domoic Acid in the water with altered water temperature or nutrients leached from agricultural lands.
Dr. Kodner’s definition of sustainability science is: using natural science methods to study the social and environmental interactions and changes, hence providing the data as a basis of better management and policy. And also, to come up with innovative solutions.
In Kenya, our class did a small insect abundance and variety survey on subsistence farms. Our investigation was brief, but we compared and critically assessed the condition of the two farms. The overarching goal of such a survey was to reduce pesticide use by relying on native species to reduce herbivory on crops. One method is to have weedy margins to agricultural plots. Reducing pesticide use reduces the amount of toxin that could be leached into streams or groundwater, which helps to ensure the sustainability of local water resources.
Insect Abundance and Variation Survey in Kenya, 2012
I am really glad that my experiences in Kenya have enabled me to contribute ideas in this class. My current research direction is to find out what aspects of orca conservation might human interest come into conflict against. I look forward to learning more about the Salish Sea and my beautiful classroom — San Juan Islands!
The 2nd workshop began with this mural mosaic
Live blog from the second workshop on “Evaluating the Effects of Salmon Fisheries on Southern Resident Killer Whales” began today (3/13/2012) in Vancouver, B.C. During this second step in a process NOAA initiated to manage chinook salmon with attention to southern resident recovery, a U.S.-Canada science panel will revisit some of the questions posed during and after the first workshop, including: population status; feeding habits; fisheries that may affect prey availability; relationship between Chinook abundance and population dynamics; Chinook needs, abundance, reductions, and food energy available. Specific goals are to discuss changes to the population modeling (FRAM, Baysian posterior estimate) and review new data on winter food sources and availability.
Most presentations include links to the slides (PDF or PPT) archived on the workshop web site. Select presentations also include a link to the audio recording of the presentation.
Day 1 (3/13/2012)
8:45 Ray Hilborn reviews science panel impressions from first workshop
His presentation summarized the types of information requests that will be addressed over the 2.5 day workshop –
– Explore the different hypotheses of why the SRKW population is so small
– How does the density of SRKW compare to the densities of KW in other areas?
– What are the legacy effects of removals for the aquaria trade?
– What else is eating Chinook and how much are they eating?
9:00 Teresa Ryan: Indigenous Knowledge Systems: An Overview
Ways that indigenous knowledge systems could increase awareness of the contribution these knowledge systems can make to natural resources management.
- There are 5 different names for eulachon (including a general term and names for successive runs, indicating to fish biologists that there are 4 runs of returning adult eulachon).
- In Tlingit, there are 3 names for 3 artistic depictions of killer whales (‘sit, or ‘kit) which may represent a “point of convergence” of indigenous knowledge and scientific recognition of three regional ecotypes: offshore, transient, and resident.
9:40 Eric Ward: Comparison of SRKW and NRKW population dynamics slides | audio (mp3)
Is the population declining?
While SRKW population has declined in some years historically, estimates of λ are overwhelmingly positive (mean λ of 1.023)
• Lambda (λ) quantifies the long term time- invariant, deterministic growth rate of a population at equilibrium
– “long term” = on scale of decades
– Replacement of females by females
– *Different than regression of population size!
• Lambda doesn’t incorporate temporal fluctuations
– Environmental and demographic stochasticity – Population age and sex structure
NOTE: juvenile survival is most important [with implications for the death of L-112 who fell in the age 2-10 year-old age class in the model]
How have actual growth rates changed?
Why isn’t the population increasing more quickly?
Possibly because there is a male bias in the southern residents…
All pods have positive growth rates, and K / L pod’s expected growth rates appear to have increased recently
Sex ratio at birth
– 45% of births since are female (44/96 v 76/140)
– NOT a statistically significant difference
Males, males, males
Reproductive and younger animals (< 20)
Stochastic birth and deaths
The male bias in the wild southern resident population may be due in part to a sex bias in the historical captures.
Why are there more males?
1. Compensation for historic removals? (male biased harvest)
2. Compensation for lower survival rate (males v females)?
3. Interaction with contaminants?
4. Trends in age of male or female SRKW?
- Moose: as mean male age drops -> fewer males
- BUT mean male age in SRKW has gotten younger
5. Older males more likely to father male offspring?
– White tailed deer, old SRKW males father lots of offspring
6. Density dependent response to slow down population growth?
– Generally opposite of what’s been observed for other long-term studies of mammals (red deer, sheep, other ungulates)
10:20 Ward continued | audio
How do southern and northern resident models (posterior distributions) differ?
SRKWs have lower fecundity — For females of a given age (23), NRKW fecundity is on average 35% higher
Mortality rates are different (not comparable as reported in 1st workshop)
NRKW are about 130% higher (not 200% as reported in 1st workshop)
Apply mixed effects models to examine variability among clans / pods / matrilines
Correlated population trends in SRKW and NRKW
Updated comparison of density dependence / covariates, with NRKW and SRKW
“Age is the major driver of fecundity, with co-variates like salmon being secondary.”
Models with density dependence (esp females) do better than salmon only models
What drives fecundity and survival? — Prey? Density dependence? Both?
SRKW and NRKW populations are correlated (e.g. drops in the 1990s are likely due to environment (and not age structure of SRKW)
1. SRKW have smaller λ than NRKW
– Lower fecundity
– Lower survival
– K/L pod have skewed sex ratio (< 40% female in recent yrs
– Fewer female births
2. Estimating random effect deviations for SRKW is difficult
– Regional (N/S) difference is better predictor
3. Fecundity: SRKW and NRKW have a similar response (+ with + salmon) – Suggests salmon difference isn’t responsible for smaller growth of SRKW4. Survival: density dependence (total females) receives most support
– DD effect is weak in SRKW, less than the effect of increasing CTC index
– DD effect is stronger in NRKW & smaller than salmon effect
– DD effect too small to explain the lower λ (or survival) for SRKW
5. Support for “Moran’s effect” (correlated dynamics between NRKW and SRKW), synchrony a result of environment because dispersal=0
– Populations correlated, drops in the 1990s likely due to environment (and not age structure of SRKW)
Whales per square kilometer in resident populations
11:10 Mike Ford — Estimating the historical size of the southern resident killer whale population | audio
Motivating questions from the science panel:
- Perhaps the SRKW population has always been small?
- How does the density of SRKW compare to the densities of KW in other areas – NRKW, Alaska, other?
Peak size reconstructed from life-tables = 96 (in 1967); +5 captures from 1962-1966; = 101 whales if all captures had livedWiles (2004) obtained a similar number (117) by adding all captures to population size in 1971
Note that the number of whales per 1000 km^2 varies and is often driven by productivity of habitats. SRKWs are about 0.9 whales/km^2, vs 1.7 for NRKWs, 0.9 for SE AK residents; SAR residents 10.7; Kenai/Aleutians 6-29; Norway 6.1-6.5.
Genetic modeling approaches
Coalescent simulation vs MCMC likelihood approximation
Hoelzel et al. (2007) used a 2-population model and found that most modern populations were much less (~10x) than ancestral populations, but divergence timing was typically ~10k years (so not very realistic for SRKW recovery goals)
New approach with a single population model, but data “are not working for me.”
New information and analysis:
- Complete mtDNA genomes are becoming available from all matrilines (collaboration with Phil Morin, John Ford and others).– Much better bounds on the ‘age’ of the SRKW population– Potential for better historical size analysis
- New nuclear sequence• ~50,000,000 base pairs of sequence from 2 individuals (K13, J26)• 10,000+ variable sites
- Microsatellite models recently added to BEAST package (Wu and Drummond 2011)
Audience comment: Remember that for SRKWs, from 80-22k years ago, the habitat was greatly reduced due to glacial ice cover.
11:45 lunch break
13:20 Larrie LaVoy — Comparison of FRAM, CTC and Kope/Parken indices, and other FRAM topics (slides not yet on-line) | audio
In 1st workshop Lavoy estimated percent reduction in Chinook food energy available to SRKW from different fisheries.
Fisheries Regulation Assessment Model (FRAM) is a tool to measure Chinook prey abundance, food energy available and the reduction in prey resulting from salmon fisheries. It is used by both NOAA and WDFW. The counterpart to FRAM for management and assessment of marine area fisheries in Canada and Alaska is the Chinook Model developed by the Chinook Technical Committee (CTC) under Pacific Salmon Commission (PSC). These two models share many common data sets for Chinook stock abundances and exploitation rate information from recoveries of coded-wire-tags.
Chinook Abundance Index (AI) is calibrated annually and is the catch-in-year divided by average annual catch in 1979-1982 (a period when many stocks were tagged and an active set of fisheries). In 2005-2008, the aggregate (across all stocks) AI ranged from 0.39 (in 2006) to 1.00 (in 2007). Note that stocks contributing to the AIs don’t all have the same importance as prey for killer whales.
Inland waters age 3-5 Chinook abundance (Jul-Sep) are typically ~1 million fish.
14:00 Angelika Hagen-Breaux, WDFW — Effects of West-Coast Fisheries on the Abundance of Mature Age Four and Five Chinook in the Salish Sea | audio
This analysis only examines mature 4 and 5 year old Chinook returning to spawn in inside waters. Stocks included any FRAM stock originating in inland waters (Puget Sound, as well as Fraser Earlies, Fraser Lates, and Lower Georgia Strait stocks).
The percent (%) increase in abundance from marine fisheries closures vary from about 3.5% for closure of Puget Sound or all U.S. coastal fisheries (about 0.5% increase of Fraser Chinook), to ~13% for closing Canadian fisheries, ~20% for closing all relevant fisheries.
Chinook abundance increases are expected under different fishery closures.
14:20 Eric Ward — Sensitivity of SRKW population growth rates to changes in salmon abundance indices (PPT) | audio (mp3)
This is not a comparison of fishing vs no fishing… (that’s tomorrow’s presentation: how much fishing impacts KW growth rate and ability to meet recovery criteria). Rather, this analysis examines fishing impacts divided up into coastal vs inland impacts.
- 21 stocks, 2 stratification approaches considered:
- Ocean Distribution: north, central, California (south)
- Migration timing: spring, summer, summer/fall, fall
Summary of results (1979-2010):
- California stocks and spring/summer stocks appear to be poor predictors of survival
- North/fall migrating stocks are better predictors of survival
- NRKW results alone give more support to fall stocks
In terms of terminal run size, the fall runs are more than 50% of the total of runs from the spring, summer, and fall. (see figure in slides)
What’s not included in fall group?• California stocks (Sacramento, Klamath)• Summer stocks• Spring stocks– Fattier (e.g. Columbia spring)– Workshop 1 result: spring stocks may be most important (Wasser, Ayres et al.)– Importance of spring stocks is not supported by our results [because the Columbia springers are not subject to regulated commercial fisheries?]
Audience (co-author?) comment: Columbia spring salmon are not in our fishery models because they’re not caught in fisheries. (They are are distributed “offshore” whereas the fishing happens along the coast. They come straight into the Columbia and the SRKWs are foraging along the coast so “they aren’t available as prey.”)
Ward: We’re not modeling predation; we’re looking at correlations.
15:30 Mike Ford — Quick review of response to other issues | audio
Comparison of diets determined from fecal samples and prey remains (scales and tissues).
Seasonal patterns in SRKW prey samples. Brad suggested that winter samples were younger Chinook (2-3 year-old).
What is known about K & L pods diet during the winter?
- Not much
- 2 samples from L pod in March (sampled off WA coast; both Columbia River Chinook)
- 18 samples from K pod in December (sampled in Puget Sound; Chinook, chum, lingcod)
Daniel Schindler: The main reason to pursue captive energetic calibration was because the energetic results presented by Noren in workshop 1 were pretty high for a predator — about 7-10%…
Ford: That was addressed that concern in Dawn Noren’s follow-up paper.
Audience: Are any data available from Keiko that would indicate how metabolic demand changed between captivity and an ocean environment?
The question and discussion was fairly extensive (~15:50-16:05) and is captured in the audio recording…
16:10 End of day 1
08:35 John Ford: Resident killer whale feeding habits | audio
Methods of assessing diet in killer whales have different limitations and benefits –
1. Chemical tracers (fatty acids, stable isotopes, contaminants) from skin and blubber biopsies
2. Prey remains in stomachs of stranded animals
3. Direct observation at the surface
4. Prey fragments (scales and tissue) recovered from predation sites
5. Fecal sampling
How reliable are prey fragments in diet assessment of resident killer whales?
1. Are surface-‐oriented prey over-represented?
We believe the majority of prey are brought to surface and broken up, usually for sharing. Adult females shared 90% of prey, males 24%, and subadults 59% (n = 213 feeding events). Salmon seem to be shared most of the time, while other prey may not be shared.
Stomach contents of three stranded residents consistent with sharing of salmonids, but not necessarily other species:
– A09: 19 Chinook, anterior bones only; 15 lingcod (only 2 large), mostly complete
– C16: 6 Chinook, anterior bones only; 5 halibut, 18 Dover sole, apparently complete
– Unknown SR female: 1 Chinook, posterior bones only
Sockeye swim at shallower depths than chinook, but rarely show up in surface samples (though sharing is documented with all salmon species taken).
• Tracking studies in Johnstone Strait indicate that Chinook swim at a mean depth of 69.9 m (± SD 57.3), max 398 m
• Sockeye tracked in same area swam at mean depth of 14.9 m (± SD 57.3)
• Sockeye rarely appear in prey samples, despite being > 4 Ames shallower than Chinook
2. Are large prey sizes over‐represented?
3. Are fish with scales that are easily shed over-‐represented?
Fragment sampling better for accurately determining proporAons of salmonids in diet, rates of prey capture in foraging bouts, and identifying when and where prey are captured
Fecal sampling better for determining presence of non-‐ salmonids, identifying prey taken over periods of up to several days
Chinook are dominant winter prey, though number of samples is small.
Winter-spring predation (by month, November-April)
Chinook are the dominant prey of SRKWs in winter-spring months, though the number of samples per month is small.
Stranded NRKW matriarch A9 had a full stomach ~Dec 7, 1990, containing:
– 18 Chinook salmon
– 15 Lingcod (only 2 large)
– 5 Greenling
– 8 English sole
– 1 Sablefish
– Various small fishes, likely prey of Lingcod
Most of the ~8 strandings had a few Chinook salmon without other fish bones, but one other had non-salmonid prey — 18 beaks of Boreopacific Armhook Squid.
Fishery impacts on Fraser and Puget Sound chinook. Distribution of fishery impacts for major stock groups. Fishery aggregates are: SEAK – Southeast Alaska, NCBC – Northern and Central BC, WCVI – West coast Vancouver Island, Geo Str – Upper and Lower Georgia Strait, PS – Puget Sound and Strait of Juan de Fuca, NOF – coastal fisheries off Washington, Oregon and California. ESC represents escapement from pre‐terminal fisheries
09:30 Robert Kope: Overview of Chinook Fisheries from SE AK to WA | audio
2008 salmon treaty reduced catch ceilings in SE Alaska and on West Coast
Plots combine commercial troll and net, as well as recreational catch.
The Fraser spring (Dome and Nicola indicator stocks) are contacted by very few ocean fisheries, but most contact is in Southeast AK fishery. WA coastal stocks are taken in SE AK (~50%), Northern BC (~20%), and off WA coast (15%?).
The SE Alaska fishery seems to dominate contact with west coast salmon populations.
9:50 John Ford: What Else is Eating Chinook and How Much are they Eating? | audio
Competion for SRKW Chinook by other predators
• Only concerned with 3–6 yr old Chinook
• Potential competitors:
» Other killer whale populations (new acoustic results suggest possible competition with NRKWs on outer WA/BC coast)
» Salmon shark – primary prey on sockeye (not much chinook)
» Harbour seal – Scat studies show lots of salmon in their diet, but dominated by pink (or 3-17% chinook)
» California sea lion – Old scat studies suggest diet is ~35% herring (salmon <~10%)
» Steller sea lion – Salmon important in their diet
North and Southern Resdident KWs detected acoustically on BC-WA coast (Riera et al, in prep)
10:00 Dave Preikshot: Ecosim modelling in Strait of Georgia | audio included in previous talk by John Ford
Ecosim SRKW biomass estimate matches the recently published age structure time series and could be an interesting metric for gauging recovery. It appears SRKW biomass is missing though total population size has been approximately constant.
Ecosim suggests there has been a decline since 1990s in the mean trophic level of predators in the Strait of Georgia.
Ecosim estimates of sea lion and harbor seal predation on salmon (based on assumption of salmon being 1-5% of their diet) suggests that their combined contribution to chinook mortality may have reached that of SRKWs around 1990.
10:20 Ian Perry: measurements of ecosystem variables, including human factors | audio included in previous talk by John Ford
There have been 3 “regimes” in the last ~40 years
10:45 Questions/discussions regarding last 3 mini talks
10:55 Chuck Parken: Pre-terminal Fisheries Impacts on Fraser River Chinook Stocks | audio
Fraser River stock representation in models (n=2) & by CWT indicator stocks (n=4) was opportunistically-based on the data available
Pre-terminal exploitation for CWT indicator stocks:
– Low for spring & fall stocks (8%-15%)
– High for summer stock (40%)
3 of 7 genetic groups did not have CWT indicator stock
Ocean distribution represented less accurately by surrogates
Audience: Which of the 3 indices we’re pondering (CTC, FRAM, Kope/Parken) are best?
Parken: We prefer the Kope/Parken index because it includes coded wire tag data while CTC and FRAM are models.
Ward: the SRKW growth rate models I’ll present this afternoon use the Kope/Parken index
11:10 Kyle Adicks: Chinook Stock Composition of Washington Fisheries Potentially Affecting SRKW Prey Availability | audio
Existing chinook fisheries are already reduced about 90% from historic levels.
Samples taken for Genetic Stock Identification (GSI) in San Juans, Strait of Juan de Fuca (Vancouver Island side only), and outer WA coast
San Juan Commercial fisheries
- 2010 – 1.96M sockeye
- 2011 – 278k sockeye, 3.67M pink
Off WA coast, commercial ocean troll chinook fishery (Areas 2-4)
- More Columbia fish closer to Columbia
- Puget Sound and Fraser fish more abundant further north (closer to entrance to Strait of Juan de Fuca
Highest Fraser proportion is off San Juan Island.
Model of chinook stock by fishery available to SRKWs (less escapement to rivers)
11:24 Craig Bowhay, NWIFC: Ancillary Benefits for SRKWs from the Coast Wide Chinook Management Regime | audio
The transition to abundance-based management and its resulting fishery structure has benefited SRKWs. Human fishing pressure has decreased and escapement has increased, though the total run size has decreased.
SRKW recovery cannot be achieved by reducing harvest. Chinook recovery is required.
Ken Balcomb: The lack of correlation between this time series and the observed changes in SRKW population and social structure suggests that something else is going on.
12:00 lunch break
13:15 Eric Ward – Fishing Impacts on SRKW Growth Rates and Management Criteria | audio (missed first ~5 minutes)
This model uses only terminal index. It manipulates salmon abundance by about 20% and looks effects growth rates (increases ~1.5%).
K and L pod’s growth is slow because of few young females. L-112 was one of only 3 females in the 0-15 year-old range.
The current probability of meeting the PSP’s goal of 95 SRKWs by 2020 is ~60%. If salmon abundance increases by 20% (from its current level of 1200 in the fall terminal index [Parken-Kope]), then the probability increases to ~80%.
If conditions don’t change:
David found a statistically significant relationship between the Abundance Indices for “Far North Migratory Stocks,” including the Upper and Mid-Columbia stocks, but then expressed surprise because he thought the ranges of those fish didn’t overlap much at all with the winter range of the SRKW. This sentiment seems to be held by other fisheries biologists here, in part because they seem to “know” that these salmon stocks spend most of their time in the “open ocean,” which presumably means in the great salmon melting pot of the Gulf of Alaska and Bering Sea.
16:00 End of Day 2
A key question is whether or not the science panel will consider management options for these stocks of big chinook on the biggest U.S. rivers — stocks which most killer whale scientists assume were historically dominant winter prey, at least for K and L pods. Are they “contacted” by fisheries that can be regulated through recommendations of the panel? Or are they only fished on the “high seas?”
Can this workshop process recommend salmon conservation actions beyond fisheries management? Will anyone mention removal of the four lower Snake River dams?
The NOAA web site leaves open the possibility that the scope could extend beyond fisheries (emphasis added):
New scientific information and analyses about the Southern Resident population and the extent of their reliance on salmon – particularly large Chinook salmon – strongly suggest that Chinook abundance is very important to survival and recovery of Southern Residents. This relationship has potentially serious implications for salmon fisheries and other activities that affect the abundance of Chinook salmon.
The letter from NOAA Regional Director Will Stelle that initiated the workshop process goes further:
New scientific information and analyses about the Southern Resident population and the extent of their reliance on salmon – particularly large Chinook salmon – have potentially serious implications for any and all activities that affect the abundance of Chinook salmon.
But he goes on to clarify that the initial focus will be on fisheries:
The questions surrounding the effects of fishing on the Southern Residents are immediately before us because the National Marine Fisheries Service (NMFS) currently is evaluating a proposed Resource Management Plan jointly developed and submitted by the Washington Department of Fish and Wildlife and the Puget Sound treaty tribes….
Accordingly, we are proposing to co-sponsor a scientific process designed to identify and summarize the status of the available science pertinent to the effects of fishing on Southern Resident killer whales and means by which key uncertainties and data gaps may be reduced. This scientific process supports the implementation of the Southern Resident killer whale recovery plan, and it will inform salmon fisheries management decisions beginning with the 2013 fishing season.
Some of us will have to remember to ask Director Stelle when similar processes will be put in place to address other activities that affect the abundance of Chinook salmon. In particular, we should be sure he’s not intentionally avoiding the controversial issue of how to manage Columbia River dams for salmon (which is familiar to him!).
For now in these deliberations about fishing impacts, one audience member put it well: All West Coast Chinook stocks should be on the table when considering the needs of the SRKWs.
8:30 Lynne Barre: Performance Metrics for Marine Mammals and Other Species | audio
8:58 Three short presentations of John Ford, DFO; Ken Balcomb, Center for Whale Research; Brad Hanson NOAA: Assessment of Potential Food Limitation in Resident Killer Whales: How, When and Where | audio (Ford, Balcomb, and Hanson)
John Ford | audio (Ford, Balcomb, and Hanson)
SRKW catch per unit effort (CPUE) goes up when local salmon indices are low…
KW CPUE decreases when salmon are less abundant.
A sighting of L pod has been confirmed well north of Haida Gwaii!
Winter – Spring Occurrence of L pod
• L pod encountered in Chatham Strait, Alaska, 1 June 2007 (Pt. Ellis, 56°34’N, 134°23’W)
• Sighted off Victoria, inbound, 9 June at 1600 (1300 km minimum in 8 days)
• Extends known range of SRKW 275 km to the north
• Overall coastal range now 2500 km
Ken Balcomb | audio (Ford, Balcomb, and Hanson)
The Center for Whale Research has conducted ~2300 surveys since the census efforts began in the 1970s, mostly in the San Juan Archipelago. Outer coast sighting network, including Nancy Black, has accumulated many sightings from central BC to Monterrey Bay. There were about 40 sightings along the coast in 2009 and that amount has approximately doubled now (2012). From 2007-2012 there were 6,094 sightings from public with 372 from outer coast (24 SRKWs).
Noted Ottawa and Algonquin ship tracks in U.S. and Canadian SRKW critical habitat, showed types of aircraft and bombs the U.S. Navy is authorized to use in their take permit, and asked NOAA and DFO to initiate an investigation of stranded cetaceans (2 beaked whales, and 2 killer whales, including L-112) along WA outer coast that he suspects are analogous to the trauma in the Bahamas he observed in beaked whales.
Brad Hanson | audio (Ford, Balcomb, and Hanson)
Passive Acoustic Recorders deployed at 7 sites (as far south as Pt. Reyes) for 4-11 months between 2006-2011. Initially used PALs (limited by 220 samples/day), but switched in 2008 to EARs (30 sec on/ 300s off duty cycle, getting about 11 months off current battery pack). Total effort Jan-June = 2972 days (doubled in 2011), mostly (>75%?) from Cape Flattery in/off-shore and Westport.
129 days of SRKW detections (57 in 2011). SRKWs were detected more often than expected in some years and locations, most notably off the Columbia River.
SRKW calls (except Js) were detected on 11 days during 157 days in 2006. First detection was not until 37 days after deployment. There were back and forth detections between Westport and Cape Flattery sites.
SRKW calls (except Js) were detected on 57 days during 180 days in 2011. There were 9 periods that exceeded a week (max 14 days) that there were no detections of SRKWs. Movements suggested by the detection sequence suggests most time spent near Columbia River and Cape Flattery, with at least one excursion for multiple days to vicinity of the Pt. Reyes site in CA.
Albion test fishery in 1981-2006 shows a peak in the spring and then gentle decline during summer. More recently (2007-2011) there are very few fish in April/May and the Albion fishery peaks in the late summer.
Since 2003: SRKWs are arriving later; are present lower proportion of days; during 2009 and 2010 pods were subdivided or only a portion of the pod was present.
Dave Bain: spring behavior of NRKWs seems distinct from later in the season (smaller groups (~7 instead of 30), faster traveling, longer daily distances (200km instead of 100km)). They seem to have two tactics for dealing with nutritional stress: increasing activity and foraging effort vs resting.
John: We need to look more closely at the Southern and Northern RKW mortality rates in the late 1990s. What drove that? What stocks were in decline then?
Process from now on:
4/30/2012 — Science panel produces first draft of report
6/15/2012 — Public comments due on draft report
8/15/2012 — NOAA/DFO comment on Draft 1, including compiled public comments
9/18-20/2012 — Workshop 3
11/30/2012 — Science panel produces its final report
12/31/2013 — NOAA finalizes Alternative Fishing Regimes report
3/31/2013 — NOAA initiates or reiniatiates ESA fishery consultations if necessary
More details in the process diagram.
What killed L-112/Victoria/Sooke? (Photo courtesy of Ken Balcomb, Center for Whale Research, copyright 2013)
The short answer for citizens of the U.S. West Coast and British Columbia is yes. In the course of training to keep our coastlines and cities safe, one of our Navies could accidentally blow up the southern resident killer whales (SRKWs), cause them to strand, or deafen them to the point of being unable to locate their favorite food — scarce and contaminated Pacific salmon.
The long answer is we don’t know yet. We have not yet been able to rule out the possibility that a resident orca known as L-112 was killed this month (February, 2012) by military sonar or an underwater explosion. Excluding such possibilities is important, in part because it would increase the likelihood that the dead female’s close relatives will return unharmed this summer, and that the SRKWs will return unscathed in future summers.
What is clear is that in February 2012 we experienced a sequence of events that should motivate us all to understand the potential risks of generating loud noises, particularly during military activities, in the habitat of marine animals that we value and that rely heavily on sound for their survival. Until we have divorced our military training and testing areas from the critical habitat of the SRKWs, and mitigated potentially harmful sources of underwater sound with attention to their annual migratory patterns, we will continue to run the risk of SRKWs suffering the type of acoustic trauma that may have killed L-112.
In this post, which remains a work in progress as of the most recent edit (3/1/2013), Beam Reach students and staff along with our collaborators aspire to review the facts of the L-112 case and assess to what extent they are causally connected. Along the way we catalog the history of military training and testing — both within the inland waters and on the outer coast of Washington — with an emphasis on acoustic observations we have helped obtain in the Salish Sea. We keep notes on what we know, what we need to know, and how hard it is to know enough to definitively connect (or disconnect) the use of military sound sources like mid-frequency active (MFA) sonar or underwater explosions with marine mammal hearing threshold shifts, changes of behavior, strandings, injuries, and deaths.
A remarkable sequence of events in February, 2012
On Thursday, February 2, 2012, the Canadian frigate HMSC Ottawa traversed the continental shelf off of southwest Vancouver Island along with another Canadian Naval vessel, the destroyer Algonquin, that also carries the SQS-510 mid-frequency active (MFA) sonar system. Based on AIS data from the ships themselves, the Algonquin returned into the Strait of Juan de Fuca within about 12 hours, while the Ottawa continued into the Pacific where (we assume) it remained until it returned to the Salish Sea and utilized its sonar on 2/6/12.
On Monday, February 6, 2012, the Canadian frigate Ottawa uses sonar in the critical habitat of the SRKWs. The training exercise may or may not have been related to a series of underwater sounds reminiscent of explosions that were recorded by the Salish Sea Hydrophone Network just minutes before the first sonar pings were detected.
On Saturday, February 11, 2012, a 3-year-old female member of the SRKW L pod known as L-112 is found dead on the beach just north of the Columbia River mouth. This occurs 9 days or 5 days after the previous events.
View 2012 sonar and L-112 stranding in a larger map
Bracketing these events are the rare sightings of SRKWs and rarer opportunities to identify pods and individuals. While SRKWs are normally only seen once or twice a month in the winter, some combination(s) of L and K pod were heard in the vicinity 18 hours after the sonar use and observed 36 hours after the sonar event for the first time ever deep within Discovery Bay.
As we gather the details of who was seen where and when, we will summarize them in the following chronology and document the evidence for each entry in the body of this post. In the chronology (a Google spreadsheet to which you may also contribute), the red background denotes sonar events, the orange background denotes potential explosive events, the blue background is for marine mammal observations, and white background is for ship locations and other events.
Outline of lines of evidence
As we explore the available and emerging lines of evidence, we will update the chronology as we document what is known in the following sections of this blog post:
- Pre-February distributions of SRKWs and other species of concern
- Feb 2-5 — Offshore Naval activities
- Pre-sonar(s) locations of SRKWs and other species of concern
- Feb 6 — Ottawa use of sonar in the Salish Sea
- Post-sonar locations of SRKWs and other species of concern
- Feb 11 — Discovery of L-112 remains, hypotheses regarding the cause of death, and subsequent findings
- History of sonar use and other military activities in Washington State
Pre-February distributions of SRKWs and other species of concern
The majority of L pod was last seen in November (?), 2011
Feb 2-5: Offshore Naval activities
Sometime during the daylight hours of Thursday, February 2, 2012, two Canadian Naval vessels began activities which remain unexplained a month later (as of 3/6/12). The destroyer Algonquin, leading the frigate Ottawa by about 20 minutes, made its way out through the Strait of Juan de Fuca about 2/3 of the way across the continental shelf and then made a U turn. The Algonquin returned to the Salish Sea while the Ottawa headed out into the Pacific (see AIS tracks below and chronology above).
The Canadian destroyer Algonquin’s ship track: Feb 2-3, 2012.
Ottawa’s track: Feb 1-6, 2012.
Importantly, the Ottawa’s was out in the Pacific (beyond the range of coastal AIS receiver stations) for 2.75 5 days (2/3/2012 3:42:00 through 2/5/2012 21:14:00). Where was this frigate during that period? We don’t know, but at typical to max speeds of 15 to 25 knots it could have made an excursion of 500 to 800 nautical miles into the Pacific — as far south as the Oregon-California border, or as far north as central Haida Gwaii.
What was the frigate doing in the Pacific? We don’t know, but upon its return it engaged in sonar training, possibly preceded by some sort of underwater detonations…
Were U.S. Naval ships in the same region operating sonar or engaged in generating explosions during the same period?
In a blog entitled “So far, sonar has not been linked to orca death“ Chris Dunagan of the Kitsap Sun reported:
I have been in touch with both U.S. and Canadian Navy public affairs officials, and both have denied that their ships were using sonar in the ocean during this time.
We should not forget to also ask carefully about any and all other Naval activities (e.g. sonar use by other entities, or potential sources of explosions), as well as other possible sources of intense underwater noise (e.g. seismic exploration).
Indeed, we should seek at least:
1) a clear explanation of what the Ottawa did do when it was in the Pacific; and
2) a confirmation of whether or not the Ottawa may have been operating in the same part of the ocean as L-112, particularly when she was killed.
Pre-sonar(s) locations of SRKWs and other species of concern
Amazingly, the calls commonly made by J pod are audible in recordings made by the NEPTUNE Canada “upper Barkley slope” hydrophone located on the outer continental shelf at the same time that the Ottawa was returning from the Pacific, steaming into the Strait of Juan de Fuca, en route to its home port of Esquimalt (just west of Victoria, BC). Searching the NEPTUNE archives for recordings made as the Ottawa passed overhead (based on its AIS transponder data) revealed a period of the recordings in which all information below 6kHz had been filtered out (by the U.S. or Canadian Navy). Near the end of the filtered data, southern resident killer whale calls are audible — even though only the harmonics extend above the high-pass filter at 6kHz.
For now, here’s an example taken from just after the filtering ceased –
This suggests the Ottawa may have (or should have?) known that SRKWs were near the entrance of the Strait of Juan de Fuca just a few hours before they began using their sonar in the eastern Strait of Juan de Fuca. Yet, Dunagan quotes the Canadian Navy (bold emphasis added):
Lt. Diane Larose of the Canadian Navy confirms that two sonar-equipped Canadian Navy ships, the HMSC Ottawa and the HMCS Algonquin, were out at sea before entering the Salish Sea at the time of Exercise Pacific Guardian.But neither ship deployed their sonar before reaching the Salish Sea on Feb. 6, when Ottawa’s pinging was picked up on local hydrophones, she said. Navy officials say they followed procedures to avoid harm to marine mammals and have seen no evidence that marine mammals were in the area at the time.
Had they heard any evidence that marine mammals were in the area? And what’s the “area” we’re talking about?
Feb 6: Ottawa use of sonar in the Salish Sea
Please begin by reading the post at orcasound.net for details about the Ottawa’s use of sonar, including sound recordings made automatically and by human listeners.
An unanswered question (as of 3/13/2012) is what caused the impulsive, reverberant sounds that were automatically detected and recorded on 2/6/2012, first at Orcasound at 4:31:05, then 4 times at Lime Kiln until 4:39:07. These sounds were recorded just 3-12 minutes prior to the first auto-detected sonar ping, but the Canadian Navy has not confirmed or denied they were associated with the Ottawa sonar training exercise. No impulsive sounds were auto-detected at those times (+/- 10s of minutes) at other regional hydrophones (Port Townsend, Neah Bay, and the NEPTUNE Barkley upper slope hydrophones.
Post-sonar locations of SRKWs and other species of concern
18 hours after the Ottawa’s use of sonar in Salish Sea, the calls commonly used by K and L pods were heard in Haro Strait.
36 hours later a group of K and L pod whales was sighted deep in Discovery Bay — where Southern Residents had never before been seen in ~40 years of recorded observations.
Feb 11: Female SRKW L-112 found dead
The discovery of L-112 on Long Beach, WA
The body of L-112 (Sooke/Victoria) was found on Long Beach, WA, about 15 kilometers north of the Columbia River. There is some inconsistency in the exact location reported in the initial necropsy report and media. The necropsy report states that L-112 “washed up just north of Long Beach, Washington on the morning of February 11.” King 5 reported that “Her body was found about a mile north of the Cranberry Beach approach.” A March 27th story in the Chinook Observer specified the location as “100 yards north of the Seaview approach,” but there doesn’t appear to be a Seaview approach. We interpret these reports to estimate the location of the body as 100 yards north of the Cranberry approach in Seaview, WA.
View Map of 2012 sonar event(s) and L-112 stranding in a larger map
Low tide on Washington’s outer coast (as predicted for Pt. Grenville, see plot below) was at 20:13 on 2/10/12. The tidal height rose until 02:37 on 2/11/12, fell until 08:46, and then rose to high tide at 14:54. If L-112′s (buoyant) body was not observed by beach walkers during the daylight hours on 2/10/12 (sunset at 19:56) and was found before noon near the high-tide line, then the time at which she reached the beach can be constrained to be during the 12 hour period between about 20:00 on 2/10 and 08:46 on 2/11. Sun rise on 2/11 was at 06:37 so it’s possible that beach observers could further constrain the arrival time.
Tidal height on the WA coast (at Pt. Grenville) around the time that L-112 was found.
When on the morning of February 11 did L-112′s body reached the beach? Can anyone confirm L-112′s body was not on the beach on 2/10/12? What was the weather like? (Is it likely that lots of people were on the beach then?) When was the discovery reported by who?
L-112 on the beach (credit?)
Close up of L-112 on the beach (credit?)
L-112 loaded on truck (photo by Bruce Williams)
L-112 was moved to Cape Disappointment State Park for the gross necropsy (photo by Bruce Williams)
Are there any pictures of L-112′s right side taken when she was on the beach or on the truck?
Initial Necropsy (Feb 12) and progress report (Apr 2)
The most mysterious part of the initial necropsy report [by Jessie Huggins (Cascadia Research), Deb Duffield (Portland State University) and Dyanna Lambourn (Washington Department of Fish and Wildlife)] is the extensive internal trauma (hemorrhaging?) without mention of blunt-force trauma (no obviously broken bones):
The whale was moderately decomposed and in good overall body condition. Internal exam revealed significant trauma around the head, chest and right side; at this point the cause of these injuries is unknown. The skeleton will be cleaned and closely evaluated by Portland State University for signs of fracture and the head has been retained intact for biological scanning.
PDF of initial necropsy web page (archived 2/3/2012)
An April 2 progress report from NOAA (archived in comments below) summarized L112′s injuries as “extensive hemorrhage in the soft tissues of the chest, head and right side of the body.” It also published (for the first time in writing?) a bound on the time of death: “Observations indicate the animal was moderately decomposed but likely dead for less than a week when found.” Previous estimates of the time elapsed between death and reaching the beach were in the range of 1-7 days, with a verbal estimate by Dyanna Lambourn during the cranial necropsy of 2-4 days.
Further details emerged in a June 2012 Seattle Magazine article through a quote of Jessie Huggins:
The biggest thing we found was the extent of the bruising; you could see it around the head and the chest and on the right side, and on the top of the lungs,” says Jessie Huggins of Olympia’s Cascadia Research Collective, a nonprofit that researches marine mammals. Researchers found no broken ribs and no signs of disease. “It looked like a healthy whale that had been through quite a bit of trauma,” says Huggins.
Where are photos of the right side of L-112?
Is there video footage of the gross necropsy?
CT scan of head (and other bones?)
Cleaning of non-cranial bones
Albert Shepherd and Amy Traxler of The Whale Museum cleaned L112′s skeleton in late-February, March, and April through a combination of flensing, sea water immersion, and the dermesid beetle colony at the Burke Museum in Seattle.
Amy and Albert clean L-112′s rib bones.
The April 2 progress report stated that they had not yet found any evidence of fractures in any of L112′s skeletal bones. It isn’t entirely clear if this statement covered the cranial bones, including the middle ears. During the necropsy there was some mention of the inner ear(s) being displaced from their attachments to the middle ear.
Hypotheses regarding the cause of death
(in order of likelihood; most-likely first)
- Primary blast injury (from a nearby underwater detonation)
- Active sonar exposure
- Ship or boat strike
- Attack by other predators/cetaceans
- (e.g. with shoreline due to acoustic disorientation)
- Other noise exposure (seismic testing or earthquake)
- Entanglement in fishing gear
- Poisoning or other ingested hazard
Primary blast injury
L-112 was killed or deafened by an underwater detonation.
Possible causes and expected signs
- Bomb dropped into Northwest training complex of the U.S. Navy
- Underwater explosion associated with readiness training of the U.S., Canadian, or other Navies.
- Underwater detonation of unexploded ordinance
- Underwater explosion from some a non-military source
Evidence for or against
Active sonar exposure
Possible causes and expected signs
Evidence for or against
Possible causes and expected signs
Evidence for or against
History of sonar use and other military activities in Washington State
Update the Beam Reach wiki entry on sonar chronology in the Salish Sea
Add pre-2003 event(s)
Was there a previous use of sonar by the Canadian Navy?
Surface ducts can occur when a mixed (isothermal and isohaline) layer of sufficient depth exists. Because the speed of sound in sea water increases with pressure, a sound of high-enough frequency made within the mixed layer will become trapped in the layer instead of spreading out into deeper water. Surface ocean mixed layers tend to be thicker during the winter due to the more vigorous vertical mixing action of breaking storm waves and wind-driven circulation.
What were S,T profiles around 2/6/12?
What would be predicted effect of surface duct on sonar and/or explosive-like sounds?
I really enjoyed the opportunity to attend a workshop on Ocean Noise in Canada’s Pacific this week in Vancouver. Foremost it was a great opportunity to meet other bioacousticians and marine listeners who I otherwise only hear about electronically. Secondarily, it was a sobering glimpse into how much more noise is likely to come the the coast of British Columbia in the next decade. My thanks to the World Wildlife Fund for funding and organizing this timely effort.
Some of the folks I really enjoyed meeting for the first time were: Paul Spong and Helena Symonds of Orcalab; Ian McCallister, Diana Chan, and Jenny Brown who are initiating the Heiltsuk hydrophone network in Bella Bella; and Janie Wray of Cetacealab; Olga Filatova, specialist in Russian orca acoustics; Darrell Desjardin of the Port of Metro Vancouver; Michael Jasny of the NRDC; and Leila Hatch of NOAA and the Stellwagen Bank National Marine Sanctuary. Discussing potential Pacific soniferous fish with Sarika Cullis-Suzuki and Francis Juanes was a treat. It was also great to catch up with: John Ford who is hearing both southern and northern resident killer whales on his NEPTUNE Canada hydrophones; Rob Williams of Oceans Initiative; Harold Yurk who showed some initial spectra of ships recorded off South Pender Island; Richard Dewey who foretold of improvements to the live VENUS Canada hydrophones; as well as Ross Chapman, John Hildebrand, Kathy Heise, and the ever-chivalrous Dom Tollit.
To get an idea of the listening effort that is going on in British Columbia, you can peruse this map of hydrophones deployed around the Northeast Pacific:
View Northeast Pacific hydrophone network in a larger map
Here is the short presentation I gave about the Salish Sea Hydrophone Network and some of our recent noise monitoring results:
“What are the effects of cars on whales?” This week, we were all asked this question by the extremely knowledgeable killer whale researcher Dave Bain. We all sat there, staring blankly and not coming up with any potential impacts. We could think of nothing. However, it turns out cars are one of the top threats to the marine mammals. Everything from oil spills, to abundance of prey, to threats to the whales from alternative energy are influenced by them.
It’s a theme that we’ve been learning a lot about in the past couple weeks. Our terrestrial environment has remarkable
Enjoying the mud at Beaverton Marsh!
effects on the marine ecosystems. It’s something that isn’t thought of that much, with the exception of direct dumping into the environment and potential contamination of groundwater. But it is a concept that deserves more attention. This terrestrial impact has been the focus of our service projects this year, and rightfully so. Last week, we helped work on the enhancement and restoration of Beaverton Marsh. Over the years, the invasive reed canary grass has taken over the wetland, which has fallen victim to agricultural overuse. The restoration project aims to help restore native species and increase the diversity of the marsh. So for a couple of hours we all sloshed around in the mud and put plant protectors and mulch on plants that had been previously planted. It was hard work, but well worth the effort. Plus, it was a GORGEOUS day, which made it very enjoyable!
Last Friday we spent the day helping out on an organic local farm. We toured the farm and learned
Sweet Earth Farms- photo by Carlos Sanchez
a bit about organic farming on the island. We talked about permaculture, which is a type of agriculture that tries to model natural processes in nature. For example, there is a heavy focus on the use of perennial plants over annual plants (which need to be planted every year). The majority of plants found in the wild are perennials, which have a very stable root system. These long, deep roots absorb nutrients more efficiently, and so generally require less maintenance than annuals, and don’t deplete the topsoil as much. For more information on the use of perennials vs. annuals, check out this article from National Geographic.
Now you might be wondering what all of this really has to do with whales. It turns out, a lot! The three main threats to the southern resident killer whales were listed as being: 1) Prey availability, 2) Vessel noise, and 3) Toxins. The terrestrial environment can have a large effect on both prey availability and toxins. Degradation of the spawning environments of Chinook salmon can limit the returns of the fish back to the ocean. These rivers are easily affected by humans and agriculture. Cattle and other livestock can erode the river and stream banks and the removal of riparian vegetation leads to decreased shelter from predators (provided by shade) and increased temperatures that could rise to undesirable levels for the cold-loving salmon. Agricultural runoff creates an influx of nutrients that can lead to eutrophication and decreased oxygen content in water bodies. Dams create barriers to salmon migration to spawning areas. All of these lead to less fish for the killer whales to eat.
Toxins also pose a huge threat to the killer whales. High on the trophic pyramid, the killer whales suffer from the bioaccumulation of chemicals (see diagram at right). High levels of DDT, PCBs, and PBDEs have been found in killer whales. These are all organic chemicals that don’t breakdown well, leading to relatively high levels in the marine environment, even for the now illegal DDT. Indeed, many pesticides are a problem. Kwiaht in 2008 found that pyrethroid pesticide levels in the San Juan County waters averaged 1-2 parts per billion, with much higher levels in some areas. Levels of 1 part per billion are known to be toxic to salmonids. Surfactants, which are chemicals used to mix water and oil, are present in nearly every man-made product. The Friday Harbor Aquarium found lethal levels of surfactants in the surrounding water.
All of these toxins come from the terrestrial environment. It is important to be conscious of what we’re pouring down the drain or dumping outside. The San Juan Islands were heavily glaciated in the last ice age, which has resulted in very thin soils in many areas. Soil typically helps to filter groundwater. This decreased filtration can lead to increased runoff of chemicals to the marine environment. It’s important to be conscious of what we’re pouring down the drain or dumping outside. Try to minimize the amount of chemicals poured down the drain. Take care of your septic system to help prevent leakage. Restoration projects help bring back native species which help balance the ecosystem. Sustainable agricultural processes help reduce the runoff of toxic pesticides and other chemicals. So be cautious, be aware, and help protect these iconic animals!